Indoor Evaporator FAN Assembly | York BQ 048, BQ 060, BQ 036

036-21508-005-A-0305

lated with a minimum 1/2” thick insulation, coated on the air- side. Aluminum foil faced insulation shall be used in the furnace compartment and be fastened with ridged fasteners to prevent insulation from entering the air stream. Cabinet panels shall be “large” size, easily removable for servicing and maintenance. Full perimeter base rails shall be provided to assure reliable transit of equipment, overhead rigging and proper sealing on roof curb applications. Disposable 1" filters shall be furnished and be accessible through a removable access door, sealed airtight. Units filter track shall be designed to accommodate either 1” or 2” filters. Fan perfor- mance measuring ports shall be provided on the outside of the cabinet to allow accurate air measurements of evaporator fan performance without removing panels or creating air by- pass of the coils. Condensate pan shall be internally sloped and conform to ASHRAE 62-89 self-draining standards. Con- densate connection shall be a minimum of 3/4” I.D. female and be a ridged mount connection.

INDOOR (EVAPORATOR) FAN ASSEMBLY

The indoor fan shall be direct drive, multi-speed, or a factory installed belt drive assembly that includes an adjustable pitch motor pulley. Job site selected (B.H.P.) brake horsepower shall not exceed the motors nameplate horsepower rating, plus the service factor. Units shall be designed not to operate above service factor. Fan wheel shall be double-inlet type with forward-curved blades, dynamically balanced to operate smoothly throughout the entire range of operation. Airflow design shall be constant air volume. Bearings shall be sealed and permanently lubricated for longer life and no mainte- nance.

OUTDOOR (CONDENSER) FAN ASSEMBLY

The outdoor fan shall be of the direct-driven propeller type, discharge air vertically, have aluminum blades riveted to a corrosion resistant steel spider bracket and shall be dynami- cally balanced for smooth operation. The outdoor fan motor shall be totally enclosed with permanently lubricated bear- ings, internally protected against overload conditions and staged independently.

REFRIGERANT COMPONENTS

Compressor:

a.Shall be internally protected with internal high-pres- sure relief and over temperature protection.

b.Shall have internal spring isolation and sound muf- fling to minimize vibration and noise, and be exter- nally isolated on a dedicated, independent mounting.

Coils:

a.Evaporator and condenser coils shall have alumi- num plate fins mechanically bonded to seamless internally enhanced copper tubes with all joints brazed. Special Phenolic coating shall be available as a factory option.

b.Evaporator and Condenser coils shall be of the direct expansion, draw-thru, design.

Refrigerant Circuit and Refrigerant Safety Components shall include:

a.Independent fixed-orifice expansion devices.

b.Filter drier/strainer to eliminate any moisture or for- eign matter.

c.Accessible service gage connections on both suc- tion and liquid lines to charge, evacuate, and mea- sure refrigerant pressure during any necessary servicing or troubleshooting without losing charge.

d.The refrigeration system shall provide at least 15°F of sub-cooling at design conditions.

UNIT CONTROLS

a.Unit shall be complete with self-contained low-volt- age control circuit protected by a resetable circuit breaker on the 24-volt transformer side.

b.Unit shall incorporate a lockout circuit which pro- vides reset capability at the space thermostat or base unit, should any of the following standard safety devices trip and shut off compressor.

c.Loss-of-charge/Low-pressure switch.

d.High-pressure switch.

e.Freeze-protection thermostat, evaporator coil.

f.If any of the above safety devices trip, a LED (light- emitting diode) indicator shall flash a diagnostic code that indicates which safety switch has tripped.

g.Unit shall incorporate “AUTO RESET” compressor over temperature, over current protection.

h.Unit shall operate with conventional thermostat designs and have a low voltage terminal strip for easy hook-up.

i.Unit control board shall have on-board diagnostics and fault code display.

j.Standard controls shall include anti-short cycle and low voltage protection, and permit cooling operation down to 0°F.

k.Control board shall monitor each refrigerant safety switch independently.

l.Control board shall retain last 5 fault codes in non volatile memory, which will not be lost in the event of a power loss.

ELECTRIC HEATING SECTION

An electric heating section, with nickel chromium elements, shall be provided in a range of 5 thru 30 KW, offering two stages of capacity - 16 KW and above on 208/230 volt heat- ers and 20 KW and above on 460 and 575 volt heaters. The heating section shall have a primary limit control(s) and auto-

Unitary Products Group